Box squaring devices



NOV. 1, 1955 c, N|TH|E 2,722,417

BOX SQUARING DEVICES Filed Sept. 22, 1.952

2 Sheets-Sheet l INVENTOR NOV. 1, 1955 c, D, E 2,722,417

BOX SQUARING DEVICES Filed Sept. 22, 1952 2 Sheets-Sheet 2 INVENTOR(710F195 Mew ATTORNEYS United States Patent BOX SQUARING DEVICESApplication September 22, 1952, Serial No. 310,775 Claims. (Cl. 271--50)This invention is an improvement in apparatus for making collapsibleboxes of stiff sheet material such as double faced corrugated board. Inthe usual procedure the sheet is cut, slotted and scored to form fourpanel sections to constitute the four peripheral walls of the box, andto form a separate flap on each end of each section which may be foldedover to form the top and bottom Walls, and a flap on the edge of onepanel which may be glued to the opposite panel.

After the cutting, slotting and scoring operations adhesive is appliedto the edge flap and the opposite panel sections are folded over tobring one edge of one end panel onto the flap on the other end panel,and these are pressed together. After the adhesive has set, the blankcan be opened to tubular form, and then the end flaps can be folded overto form the top and bottom of the box.

It is important from the standpoint of appearance, as Well as strength,that one edge of the blank be parallel to and centered on the edge towhich it is to be glued.

In feeding the folded blank to the gluing mechanism it is usuallyadvanced by a supporting belt and guided by parallel side walls whichmay be adjusted toward and from each other. As these guide walls arenormally stationary and the blank travels between them, they should notexert any appreciable frictional resistance to the movement of theblank, as the blank is advanced solely by the frictional engagement withits conveyor belt.

If the box be a deep one the fold lines between the side walls are long,and there can be little or no skewing of the blank in respect to theguide walls. On the other hand, if the box be large and shallow, thefold lines between the wall sections will be short, and as some slightclearance is desirable between the fold lines and the guide walls theblank may be advanced to the gluer with the abutting or overlappingedges of the blank out of proper register, and may be slightly askew. Inthat event the resulting box may have an unsatisfactory appearance aswell as a weaker structure.

The main object of the present invention is to provide means whereby theposition of the blank is automatically shifted, if necessary, to bringthe edges which are to be glued together into a line parallel to thepath of movement of the conveyor.

In carrying out my invention I in the path of movement of each of theside fold lines or closely adjacent thereto. These stops are so mountedand controlled that each may be moved by the blank, but only for alimited distance, and only until the other stop has been moved the samedistance. Thus, if the folded blank be somewhat askew, one stop will bemoved for a limited distance by one edge of the blank, but will move nofarther until the opposite fold line has engaged the other stop andmoved it to a position even with the first mentioned one. Then bothstops are automatically released, and the blank which has been properlyaligned or squared will advance to the gluer or other means for closingor completing the corner joint.

provide two stops, one

In the accompanying drawings I have shown only one embodiment of myinvention, but it is to be understood that this form, although apreferred one, is merely illustrative of the invention. In thesedrawings:

Fig. 1 is a perspective view of a machine embodying my invention.

Fig. 2 is a perspective view, the target and the control means therefor,and with parts broken away.

Fig. 3 is a side elevation in Fig. 2.

Fig. 4 is a somewhat diagrammatic showing of the blank advancing means,and

Fig. 5 is a wiring diagram of the control parts.

The blank may be of a conventional form and include four panel sectionsA, B, C and D, and a flap D' with scored lines therebetween, and withthe sections A and D folded over onto the sections B and C so that oneedge of the section A may be pressed onto the flap to which adhesive hasbeen applied. The opposite edges of the blank have slots in line withthe fold lines to permit one pair of opposite end flaps to be foldeddown after the other pair of flaps have been folded over. Thus the foldlines F and G between the side panels are shorter than the blank, andfor a large shallow box the opposite of certain of the parts shown edgesof the folded blank may be comparatively short.

As there may be a slight spacing between the vertical walls 12 whichterminal slotted portions of the fold lines and the parts of the machinewhich guide the folded blank, the blank may be slightly askew.

I have illustrated my invention in connection with a common type ofgluer in which the folded blanks are advanced by frictional engagementwith a belt 10 supported on pulleys or drums, only one of which, 11, isThe blanks are guided between shown in dotted lines.

may be adjusted toward and from each other, and in accordance with thedistance between the fold lines F and G of the blank.

Carried by each guide Wall 12 is a control mechanism which is shown indetail in Fig. 2, and which acts to stop the blank at a fold line if theblank be somewhat askew and one fold line is in advance of the oppositeone, and also acts to release the blank when it has been properlyaligned with the belt and guides.

In the form illustrated each control unit has a frame including a base15 which may be bolted on a flange of the guide wall 12, and on thisbase is a vertical flange or bracket 13 in which is journaled a rockshaft 14 carrying a target 16 on the opposite side of the wall 12 and inthe path of movement of the advancing blank. Mounted on the rock shaft14 is means for controlling the movement of the target. This includes adepending arm 17 to which is connected a spring 18 which resists butpermits swinging of the target when a box blank engages it.

If one edge of the folded blank be in advance of the other it isimportant to stop this edge until the other catches up. For this purposethere is provided a stop in the path of movement of each arm 17, andwhich temporarily permits only limited movement of the arm, and meansfor simultaneously removing both stops after both arms have reached thelimit of their free movement and the front edge of the box blank is atright angles to its path of movement.

In the form illustrated there is provided an electromagnet 20 for eachtarget, and having a solenoid, armature, or other part 21 movable intoand out of the path of the arm 17. When the circuit of the magnet isopen a spring 22 pushes the part 21 of the solenoid into the path ofmovement of the arm 17 so that neither the arm nor the target 16 can bemoved more than a short limited distance by the blank. Thus, if one endof the partly in section, showing front edge ofthe blank be ahead of theother, that end will" be stopped until the other end reaches and" movesthe other target.

For controlling thecircuits of the. magnets 20 which withdrawthe stops,each arm 17 has. or engages a. push button 2'4'for operating a switch2'5in acasinglfi'. As. shown in the wiringdiagram, Fig. 5;,the twoswitches 25 which are operated by the swinging ofthe arms. 17; areconnectedi'n series, and the armatures of the'magnets 20 are connected.in parallel with. each. other but in series with the switches.

If the blank be slightly askew as it advances it will first engage andmove one target 16, but only to a limited extent, and'until the arm 17engages stop 21 andreleases the. push button 24 of one switch 25, thusclosing it; Thus this end of the edge of the blank will be stopped butthe other edgemay continue moving by the dragging action of the conveyorbelt, and until it engages itstarget and closes itsswitch 25'. When bothswitches have been closed both of the armatures will be energized andboth stops 21 will. be pulled back out of. the path of theircorresponding arms 17, and the two targets can freely swing out of thepathof the-blank. The blank will advance with its front end at rightangles to its path. of. movement, and the box will be closed. With oneedge of' the.b1ank. properly. registering with the flap to which it is.to be secured;

II have not illustrated in detail the means for securing the edges. ofthe blank together, as these form no part of my invention and'may be ofconventional form. The machine is set up, by adjustinggthe guide. walls12 to bring theLflap D in proper position inrespect to the glueapplicator and to the shoe 30' which presses the wall A down. onto. theflap and thussecures them together.

All of the. operating parts shown in Fig. 2 and on opposite. sides ofthe machine arev preferably protected and concealed by casings 26 whichare detachably secured to the base plates15,.as shown in Fig. 1. In thatfigure. the shoe 30'is shown offset laterally as it might be temporarilyto permit adhesive to be applied or dried adhesive thereon to bemoistened, before the panel A is moved down onto said adhesive coatedflap D.

Having thus describedmy invention what I claim as new and desire tosecure by'Lett'ers Patent is".

1'. A machine for advancing a folded box blank to means for securing theopposite edges together, said ma-. chine including means forfrictionally engaging and advancing the blank, a pair of stops spacedapart. laterally in the path of movementofthe blank and each movable.byand with the blank, meansfor limiting the free movement of said stops,electro-magnets for simultaneously releasing said stops, and means forenergizingbothmag nets when both stops have reached the end of theirrespective limited' free movements.

2. A machine for advancing a folded box blank to means for securing theopposite edges together, said machine including means frictionallyengaging the folded blank and advancing the same, a pair of stops in thepaths of movement of the: opposite edges of the folded blank andmovableby theblank, means forlimiting the free movement of the stopswith the blank, separate electro-magnets for.rendering.saidimeanstinoperative; and means forsimultaneously energizingbothmagnets-when both of said stops have reached the limit. of theirfree movement with they blank.

3. A machine for advancing a box blank with its opposite edgesjuxtaposed, to means for: securing said edges together, said machineincluding means frictionally engaging the folded blank and advancing thesame, a pair of targets in the path of movement of the opposite edges of'the folded blank,,each target having limited free movement with theblank, an electric circuit includinga pair of magnets. in parallel and apair of" switches. in serieswith bothmagnets,v and" means for closingeach switch upon a predetermined movement of its corresponding, target,.whereby both targets arereleasedonly upon pre-- determined movementofboth targets and the closing of both switches.

4.. Mechanism for advancing a folded box blank, including aipair' ofstops one in the path' of'movement ofea'ch of the opposite fold' linesof the blank, means for limiting, the movement of each. stop, anelectric circuit including a pair of electro-magnets for releasing saidstops said electro-rnagnets being connected in parallel in said circuit;and'separate switches both in series with both of: said magnets andoperated by said stops, whereby said magnets are simultaneouslyenergized when both stops have been moved to the. same limited distance.

5. A machine for advancing box blanks, including separate. stops spaced.apart across the path of'movement of. the. blanks, each stop havingIi'mited'free movement" in respect to. the other and with the advancingblank, an electric circuit having separate electro-magnetsconnected inparallel; eachactingto release a separate. one" of said stops; and meansfor controlling said circuit to energize saidelectro-rnagnets'simultaneously.

References Cited in the' fileof this patent UNITED STATES'PATENTS

